Brake device



March 1s, 1924; l,487,652

J. L. GAGET-RAGOT BRAKE DEVICE Filed Jan. 25 1922 3 Sheets-Sheet 1 March 1.8 1924.

J. L. GAGl-:T-RAGOT BRAKE DEVICE Filed Jan. 25, s sheets-shea 2 Hugs.

March 18 1924. 1

J. L. GAGET-RAGOT BRAKE D'EvIcE Filed Jan. 25. 1922 3 sheets-sheet 5 173 WMM HZ'HS.

Patented Mar. 18, 1924.

UNiTl-:D STATI-is 1,487,652 PATENT OFFICE.

JEAN LOUIS G-AenT-RAGOT, oF Panis, `FRANCE.

BRA'E nEvIcE.

Applicatimi mea January 25; 1922. seri'aiN. 531,743.

To all ywhom t may concern.:

Be it known that I, JEAN LOUIS GAGET- Rasoir, a citizen of the Republic ofFrance, residing at lll, Boulevard Exelmans, Paris, France, have invented certain new and useful Improvements in Brake Devices, of which the following is aspeciiication.

The present invention relates to a braking system and device, more particularly adapted for vehicles of all kinds, and especially for railroad vehicles, said devices being arranged in such a way as to produce a. braking action varying with the load of said vehicles.

Said system and device have :mainly for their object to improve considerably thesecurity and the eilciency of the4 braking action of vehicles in general and of freight train carriages in particular.

The use of the system and device of the present invention enables the obtention of a maximal output of the apparatus now in use.

In order to obtain this result, the brake shoes (or someV of them) are submitted to braking efforts varying with theload. The variation in the effort is produced automatif cally by a member Which is controlled-by the changes in the deflection of the suspension springs of the vehicle, saididelection being proportional to the load. Undertlie action of said changes, the pressureof the brake shoes on the Wheels can -be maintained constant orcan vary according toa given ratio. Y a f Said system and'devic'es can azlsobe are ranged in such a way that all reactions, even those resulting from the strongest braking efforts, can in no case react on the suspension springs of the vehicle, and that the connection between the axle bearing. and the eort changing member is merely a transmission relay. g

Further, the displacement of themember controlled by the variation in load'o-thevehicle is effected by means of ai-lever provided with a slot of such shape.and outline1-ias to take up the Wear of the brake shoes as it .is produced. q

In the following description it is' `assumed that the brake used worksyvvith compressed air, but it -is well. understood thatthebrake couldas -well Vbe acted upon; by` -a vacuunior by anypth'enmo'tive power; .it is;-,"a ls o;ob-y viousng that -tl1e ilyllton.; also azp'fl,... -..im brakes using no Huid, such as mec anical,

electrical, electro-magnetic brakes or the like. l

. The annexed drawings show by Way of eX- ample a braking systemaccording to the invention, Worked by'compressed air. f

Fig. -l is a-side view partlyin vertical seotion, assuming vthat the vehiclebe empty; Fig. 2 is a vertical section of a buffer;

Fig. 3 :isa plan view corresponding to Fig. 1, vthe air cylinder being invsection.

Fig. is-aside view of the system, the

vehicle being 10aded.= Fig. 5 isa partial ,view aty an enlarged effort gchanging member of g the device.

1 denotes a brake cylinder. by; which .the

said-,cylinder ispivota'lly connected at() to scale, of the camarrangement or braking one end of a leven 3.- The backend of cylinl der l bears the xed pivotfO of a, lever 2. The levers 2 and 3 are unitedby a connecting rod v50. The pivotal y'connections 'of the levers 2 .and 3 With the connecting rod 50 are obtained by rmeans of pins 16 .and sliding membjers 7 moving in `slots aof levers 2 and 3 and a1 of the connecting rod 5 O, The slides of the: levers 2. and are. directed at a certain anglefromthose `Jformed in the connectingrrod ,50. Saidarrangement has for 1 its-.object to` maintain constant theL piston stroke of the brake cylinder, whatever the variation oft he lever arms 2 and 3 may be; the connecting, rods 51 and 52,v iixed respectively onfthe ends of the levers 2 and 3,.serve fortransmitting the braking eiort to the brakezshoes.. 1 ;-y

. According to the. cross axis of the connecting rod 50 is lodged amember producing the changes in the braking eiort and made up as 1 Two bearings 14, 'also used as thrust members, are fixed 4lby means v,of bolts between the two ansesormllg the'comwctns mmf ber 5.03; a shaft 9.. tra.\ ffr1sei4 both bearings 14 andnmsaid Shaft are xedtrvqvppoed flanges, 6 foilfriihgaadonhle amaeah Q-fiheopposed iangesgcomprise's a-series of corresponding steps, .betvveen. qv\rhich, y and.- in A`engager'nent Wthf-areadsposed tw@ movablethrust members.rxedftcjlevers by :pivots 1.9, The distance fbetneenathe corresponding.; Steps @rte-the opposed-flanges "is i .11st, ,isulio-ent. .to permit. .-theflocati'on nf fthe/...thrust members, the .--ftao danses being. however, slightly laterally lshifted relative to eachother in order to provide a small clearance, such as C (Fig. 5), enabling the thrust members to pass from one step to the next. The arrangement is such that the thrust members will only be displaced'by rotation of the cam, to the exclusion of any reciprocal movement, (reaction of the thrust member) upon the cam. Further the levers 4 turn on pivots 15 fixed in connecting rod 50 and are in engagement, at their opposed ends, by means of a longitudinal slide a2, with the short shafts 16 which connect, by means of sliding members 7, the levers 2 and 3 with the connecting rod 50. Vrl`hey levers 4 are pierced with a hole b and the connecting rod 50 with a hole 1. Said holes coincide when the vehicle is empty; when for some reason it is not intended to use the system, two pins' can be introduced in said holes and the connecting rod 26, the purpose of which will be described hereafter, be detached.

The levers 2 and 3 bea-r abutments 42 and 44 t-he purpose of which is to maintain the connecting rod 50 in a determined position by means of its cam surfaces 53. i A spring 43 fixed by its endl tothe abutments 42 vand a spr-ing 45 secured at one end to vthe lconnecting rod 50 and at the other end to a fixed point of the vehicle, act for returning the whole device to the position of rest, in engagement with the abutments 46, after every release of' the brake.

On the shaft 9 isl mounted a lever 10 having a slot c of predetermined shape or outline, the purpose of which will be more fully explained later on and said slot is connected with an equalizer 11 by means of a crank pin 56. The equalizer 11 is pivoted at 13 on a supporting member 12 fixed by bolts under connecting member 50. The connecting rod 26 is connected by means of a pin 25 to the equalizer 11 and by 4means of a pin 27 to a lever 28 fixed, together with a fork-shaped lever 30, on a-shaft 29, the two levers 28 and 30 being vset at a predetermined angle.` The other ends of lever 30 are connected by means of pins 55 to a buffer 31 which is connected with the axle bearing 37 of the vehicle by a, connecting rod 35 and a pivot 38.`

The fixed points of the above described mechanism being attached to the vehicle frame. it is obvious from this arrangement that whenever the load increases, the distance between pins 29 and 38 is reduced, on account of the deflection of the suspension springs under the influence of the increasing load.

Fig. 4 shows the whole device, the brake being released and the vehicle completely loaded. In this position, the reduction of the distance between 29 and 38', resulting from the deflection of the suspension springs under the action of the load, determines the rotation of the lvers 28, 30 on shaft 29. By this movement, thefconnecting rod 26 turns the equalizer 11 on its pivot 13 and the crank pin 56 carries with it the lever 10.v The rotation of the latter is transmitted by shaft 9 to cam 6, the steps of which produce a displacement of the thrust members 5. Said displacement acts for turning the levers 4 on pins 15, and consequently for displacing the. pins 16 towards the ends of levers 2 and 3 connected to the rods 51 and 52, and thus increasing the ratio of the lever arms 2 and 3 by displacement oftheir centres of rotation.

In this movement, the angle between the slots al and the slots a acts for bringing nearer together the levers, thus reducing the play of the brake shoes. It must be noted that cam 6 occupies the intermediary position when the vehicle is completely loaded and the brake released; thus, suflicient play is leftl for the brake shoes in service. of the device without increasing the piston stroke of the brake cylinder, in order to increase the braking effort.

The second period of increase of the braking elfo-rt corresponds to the putting on of the brake. Vhen air under pressure isv admitted in cylinder 1, the piston carries with it lever 3, whichvturns on its pivot 16 and displaces connecting rod 52 to the right, until the brake shoes come into engagement with the wheel. Said brake shoe acting then as fixed point, the piston stroke is continued and produces a translation movement of the connecting rod 50 and of the parts attached to it. Simultaneously, rod 51 is displacedl to the left, until the corresponding shoe engages the wheel, and the pivot pin 25 having become fixed, the pivot pin is displaced a predetermined amount, this resulting in a complementary movement of the equalizer 11 on its pivot 13, said movement being transmitted to lever 10 by crank pin 56. The special outline of slot c of lever 10 then intervening, the cam 6 is further rotated. In this movement, steps of different heights engage the thrust members 5, so that the levers 4 are rotated on their pivots 15; the other ends of the levers v4 thus determine the final displacement of pivots 16. The second period of variation of the ratio of lever arms 2, 3 is thus obtained. v l During said second period, the important result is obtained of bringing the connecting rods 51 and 52 nearer together, on account of the angular position of the slots a of the levers 2 and 3 with respect to the slots al of vconnecting rod 50; said arrangement enables Said arrangement enables the usey y vmarinara l3 positions, and in this-reverse movement the pivot pin 13, eects a tilting of equalizer 11 on its pivot 25; in this movement, lever 10 is brought back to its preceding position and cam 6 is also brought back to its initial point, this returning the system of abutments 5, levers 4 and pivots 16 to the position shown in Figs. 1 and 3 or in Fig. 4.

As previously stated the slot C of lever 10 is of particular shape and comprises essentially a straight radial l,part and a part inclined to the first one, the inclination being directed in the sense of -rotation of cam 6 which correspond to the leading of the vehicle. This arrangement has for its object to provide for `an increasing angular displacement of the lever 10, and consequently of cam-6 when the pin 56 is conductedby the said inclined part,that is to say, when the vehicle is completely 'l loaded and the brakes applied.v At this moment, in case of wear in the shoes of the brakes, the tilting movement ofthe lever "11 will be increased, and owing to the resultingl more increased rotation of the cam 6,'the braking levers 2 and 3 correspondingly move nearer together so that the stroke of the brake cylinder piston is practically maintained constant;

The buii'er 31 serves for transmitting the movements created by the deection of the suspension springs to the connecting rod 26 by means of levers 30 and 28.

Said buer comprises a spring 57 the initial tension of which is sufficient for4 overcoming the passive resistances of the systemy (the brake being completely released). When the train is slowing down, i. e., the brake being lightly applied, the vehicle passes on the rail joints, the axle reacts on the suspension springs and there is a tendency to a displacement of point 27. The cam being entirely irreversible, this movement could not possibly be absorbed. At this moment, spring 57 absorbs the successive reactions.

Two other cases can be considered.

1. When loading a car, the brakes of which are applied, the spring 57, having a suiiicient range, will absorb the whole movement; as soon as the brake is released, all parts will return to their initial positions.

2. IVhen unloading a car, the brakes of which are applied, the parts operate in the same manner.

The above described device embodies a system of levers by which the braking eiort can be varied, although the motive effort remains constant, by means of the load or, in a more general way, of .an auxiliary eiort which is inde endent of the motive Keort, acting throug the irreversible step. cam above described. i

The application of the system to the special case of a compressed air brake is given merely by way of example, and it is well understood that the invention come prises not only the application on other brake systems, using any fluid or being controlled mechanically, electrically, magnetically, or otherwise, but also on any effort transmitting system.v

The irreversible step cam can differ from the vcaln above described; the arrangement of the steps given by way of example, their shape and their succession can vary accordingto the intended purpose. The irreversibility of the cam is due to the fact that the direction of the displacement of the movable member controlled by the cam is at right angles` from the plane of the Asteps of the latter; this eliminates any tangential component enabling the movable member to drive the cam. c

Such a cam can be applied to any transmission of movement, and especially to the displacement of the rocking point of a lever.

Having now described my invention, I declare that what I claim is:

1. In a braking device, acam actuated by the variations of theV load, a connecting member on which said cam is mounted, and twov brake controlling levers, oscillating in opposite direction, also mounted on the connecting member and between which said cam is mounted.

2. Ina braking device, a cam actuated by the variation of the load, a connecting member on which said cam is mounted, brake controlling levershaving slots, said connecting member having slots, the first named slots being set at a certain angle to the second named slots, pivotal connections between said levers and said connecting member, the said connections being movable in said slots.

3. In a braking device, a cam actuated by the variation of the load, a connecting member on which said cam is'mounted, brake controlling levers having slots, said connecting member having slots, the rst named slots being set at a certain angle to the secon-d named slots, pivotal connections movable in said slots and means actuated by the cam for displacing the said pivotal connections.

4. In a braking device, the combination of an actuating device, brake shoes actuated thereby, intermediate levers for transmitting the motive power from the first named device to the brake shoes, said levers being mounted on a connecting member provided with slots, said levers having slots angularly disposed to the irst named slots, pivotal connections in the said slots, levers actuated by cam for displacing said pivotal connections, the cam mounted on the connecting member and provided with opposed flanges, each flange of the cam having series o steps, the steps of one flange corresponding to the steps of the other iange and thrust members of the actuating pivotal connection levers comprised between the flanges of the cam.

5. In a braking device, the combination of an actuating device, brake shoes, actuated thereby, intermediate levers for transmitting the motive power from the first named device to the brake slices, ysaidlevers mounted on a connecting member provided with slots, saidy levers having slots, angularly disposed to the first named slots, pivotal connections in the slots, leversactuated by a cam for displacing said pivotal connections, a cam, a lever mounted on said cam and actuating the latter, a slot in said lever and lneans connected with the slot for actuating said lever. n i

6. In a braking device, the combination of an actuating device, brake shoes actuated thereby, intermediate levers for transmitting the motive power from the first named device to the brake shoes, a connectingmember ,provided with slots, saidv levers having slots angularly disposed to the first named slots, pivotal connections inthe slots, a cam, levers actuated by cam for displacing the said pivotal connections, a lever mounted on the cam and actuating the latter, a slot in said lever, sai-d slot comprising a Lstraight part and a part inclined to the first one in the sense of rotation of the cam which corresponds to the direction of movement of the cam incident to the applicationhof the brakes, and means connected with the slot for actuating said lever.

7 In a braking device comprising an. actuating device, brake shoes actuated thereby, intermediate levers for transmitting the motive power to the brake shoes, a connecting member provided with slots, said levers having slots, pivotal connections in the slots, a cam and means for displacing the pivotal connections and actuated by the cam, said cam mounted on the connecting member and abutments for securing the position of rest of the said connecting member.

8. In a braking, device comprising an actuating device, brake shoes actuated thereby, intermediate levers for transmitting the motive power to the brake shoes, a connecting member between said levers, a cam mounted on the said comiecting member, levers actuatingthe cam, one of ysaid levers oscillating about a fixed point ofthe vehicle frame and connected by one of its ends to a point of one of the axle bearings.

9. In a braking` device comprising anv actuating device, brake shoes actuated thereby, intermediate levers for transmitting the motive power to the brakeshoes, a connecting member betweenV said levers, a cam! mounted on the connecting member, levers actuatingthe cam, one of the -said levers oscillating about a fined point of the vehicle frame and means, Such as an elastic. buffer, connecting one of the ends of the last named lever to a fixed point of one of the axle bearings. Y In testimony whereof I affix my signature.

JEAN LOUIS GAGET-RAGOT. 

